WO2013082951A1

WO2013082951A1 - Electrode structure for laminated metallized thin film capacitor

Info

Publication number: WO2013082951A1
Application number: PCT/CN2012/080132
Authority: WO
Inventors: 朱健; 林晋涛; 陈国彬
Original assignee: 厦门法拉电子股份有限公司
Priority date: 2011-12-07
Filing date: 2012-08-15
Publication date: 2013-06-13
Also published as: DE112012005147T5; US20140301019A1; DE112012005147B4; JP2015503236A; JP5984097B2; CN102543438A; CN102543438B; US9281122B2

Abstract

An electrode structure for a laminated metallized thin film capacitor, including at least two metallized thin films (1) laminated together, several curve gap strips (15) not covered with a metal coating and having a certain width also being provided in the direction of the laminated metallized thin film capacitor core slice on each metallized thin film (1), so as to locally or completely space apart adjacent metal coating units; the middle portion of the curve gap strip (15) being in the shape of a recess, two sides of a recess (151) forming an alternately distributed shoulder shape; in two adjacent curve gap strips (15), the endpoint at the most raised area of one curve gap strip (15) at least entering into the recess (151) of another curve gap strip (15). The structure enlarges the insulation distance between metallized electrodes with difference potential on the capacitor core slice, and can improve the slice pressure tolerance of the laminated metallized thin film capacitor core.

Description

Electrode structure of laminated chip metallized film capacitor

Technical field

This invention relates to electronic components, and more particularly to an electrode structure for a laminated metallized film capacitor.

Background technique

A film capacitor is one of the capacitors. It is a capacitor with superior performance. It has the following main characteristics: no polarity, high insulation resistance, excellent frequency characteristics (wide frequency response), and low dielectric loss. Due to its small size and large capacity, film capacitors have a wide range of applications and can form different series of products, such as high specific energy storage capacitors, anti-electromagnetic interference capacitors, radiation-resistant capacitors, safety film capacitors, long-life capacitors, and high reliability. Capacitors, high voltage full film capacitors, etc.

One form of structure of a film capacitor is made of a metallized film which is formed by vacuum evaporation of a thin layer of metal on a plastic film which is used as an electrode.

In the prior art, two or more metallized films and/or a plurality of light films are wound into a capacitor core mother roll by a winding device, and after being processed by a gold injection process, the chips are cut into individual laminated capacitors by a cutter. The core is finally made up of a capacitor using a laminated capacitor core. This laminated metallized film capacitor has a defect. The position of the cut surface of the capacitor core, the insulation distance between the metal electrodes of different potentials is only the thickness of the medium between the electrodes, and the thickness is several micrometers to several tens of micrometers, depending on the coating. The coating material on the cut surface is insulated to ensure the withstand voltage, and the pressure resistance of this cut surface is not too high.

Summary of the invention

The object of the present invention is to overcome the deficiencies of the prior art and provide an electrode structure of a laminated metallized film capacitor. By special design of the electrode structure, the metallization between the different potentials of the capacitor core is increased. The distance can improve the section pressure resistance of the laminated metallized film capacitor core.

The technical solution adopted by the present invention to solve the technical problem thereof is: an electrode structure of a laminated metallized film capacitor, comprising at least two metallized films laminated together; adjacent upper and lower metallized films in the longitudinal direction That is, the vertical film edge is stacked in a staggered state with a predetermined wrong edge width; each of the metallized films respectively includes a conductive metal plating layer and an insulating dielectric layer, and the conductive metal plating film is coated on the insulating dielectric layer; Each of the metallized films is provided with at least one void strip which is not covered with a metal plating and has a width along the lateral direction, and the void strip constitutes a residual edge of the metallized film.

On each metallized film, a plurality of curved gap strips which are not covered with metal plating and have a certain width are arranged along the cutting plane direction of the laminated metallized film capacitor core to connect adjacent metal plating units Partially spaced or completely separated; the curved gap strip has a concave shape in the middle, the two sides of the recess form a shoulder shape with a misaligned distribution, and the opposite direction of the recess opening is convex; in the adjacent two curved gaps In the strip, the most convex end of one of the curved void strips enters at least the recess of the other curved void strip.

The notch shape of the curved gap strips of the adjacent upper and lower two metallized films may be in the same direction or different directions of the notch openings; that is, the notches may be oriented differently in the same direction.

The adjacent upper and lower metallized films, the metal plating of the upper metallized film is connected to the first electrode, and the metal plating of the lower metallized film is connected to the second electrode, and the first electrode is on the cut surface There is a predetermined distance between the second electrodes.

The width of each curved gap strip is equal or unequal, and the width of each curved gap strip is greater than or equal to 0.1 mm; that is, the curved gap strip may be of equal width or unequal width, and the width is greater than or equal to 0.1mm.

The curved void strip is composed of a first curved void strip, a second curved void strip, a third curved void strip, and a fourth curved void strip that are integrally connected in series.

The curved gap strip is disposed along a cross-sectional direction of the laminated metallized film capacitor core, the cut surface direction and the longitudinal direction are at a predetermined angle, the cut surface direction is consistent with the longitudinal direction, and the preset angle is zero degrees; the cut surface and the The first curved void strip, the second curved void strip, the third curved void strip, and the fourth curved void are formed after the curved gap strip is reversely twisted by the predetermined angle, and the tangent direction is consistent with the longitudinal direction. The article satisfies the following conditions:

The fourth curved type gap strip is a curved section between a preset position in the curved gap strip to the trailing edge of the metallized film, and the second curved type gap strip is a curved type gap strip after the fourth curved type gap strip is removed The curve segment between the endpoint at the far left of the segment and the endpoint at the far right.

The invention has the beneficial effects that a plurality of curved gaps which are not covered with metal plating and have a certain width are provided on the surface of the laminated metallized film capacitor core on each metallized film. a strip for partially or completely separating adjacent metal plating units; the curved gap strip has a concave shape in the middle, and the two sides of the recess form a shoulder shape which is misaligned; in the adjacent two curved gaps In the strip, the most convex end of one of the curved void strips enters at least the recess of the other curved void strip. The structure increases the insulation distance between the metallized electrodes of different potentials on the cut surface of the capacitor core, and can improve the cut surface pressure resistance of the laminated metallized film capacitor core.

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments; however, the electrode structure of a laminated metallized film capacitor of the present invention is not limited to the embodiment.

DRAWINGS

1 is a schematic view showing a state in which two upper and lower metallized films of the present invention are separated according to the first embodiment;

Figure 2 is a front elevational view showing the laminated state of the upper and lower two metallized films of the first embodiment of the present invention;

Figure 3 is a left side cutaway view showing the stacked state of the upper and lower two metallized films of the first embodiment of the present invention;

Figure 4 is a right side sectional view showing the stacked state of the upper and lower two metallized films of the first embodiment of the present invention;

Figure 5 is a schematic view of the first metallized film of the present invention;

Figure 6 is a schematic view showing the configuration of a curved type void strip of the present invention;

Figure 7 is a schematic view showing the following one metallized film of the present invention;

Figure 8 is a schematic view of a metallized film of the present invention (the cut surface and the longitudinal direction are at a predetermined angle);

Figure 9 is a schematic view showing a metallized film of the present invention;

Figure 10 is a schematic view showing the state in which the upper and lower two metallized films of the present invention are separated according to the third embodiment;

Figure 11 is a cross-sectional view showing a state in which two upper and lower metallized films of the present invention are laminated in the third embodiment.

detailed description

Embodiment 1 Referring to FIG. 1 to FIG. 7, an electrode structure of a laminated metallized film capacitor of the present invention includes at least two metallized films laminated together; adjacent upper and lower metallized films Laminated in a longitudinal direction in a staggered state having a predetermined wrong side width, the film widths of the upper and lower metallized films are equal, and the upper metallized film 1 and the lower metallized film 2 are laminated to have a wrong width. Each of the metallized films comprises a conductive metal plating layer and an insulating dielectric layer, and the conductive metal plating film is coated on the insulating dielectric layer. The upper metallized film 1 comprises a conductive metal plating layer 10 and an insulating dielectric layer 100. The conductive metal plating layer 10 is coated on the insulating dielectric layer 100. The lower metallized film 2 includes a conductive metal plating layer 20 and an insulating dielectric layer 200. The conductive metal plating layer 20 is coated on the insulating dielectric layer 200. The strip metallized film is provided with at least one gap strip which is not covered with a metal plating layer and has a certain width along the lateral direction, and the gap strip constitutes a margin of the metallized film, and the upper metallization is thin. 1 has a left side 101, the sheet 2 is provided with metallization film 201 left side;

On each metallized film, a plurality of curved gap strips which are not covered with metal plating and have a certain width are disposed along the longitudinal direction to partially or completely separate adjacent metal plating units, and the upper metal is separated. The film 1 is further provided with a plurality of curved void strips 15 which are not covered with a metal plating and have a certain width along the longitudinal direction to partially or completely separate adjacent metal plating units, and a plurality of curved patterns. The gap strip 15 forms a grid curve on the metallized film 1. The lower metallized film 2 is further provided with a plurality of curved gap strips 25 which are not covered with a metal plating and have a certain width along the longitudinal direction to be adjacent. The metal plating units are partially spaced or completely separated, and a plurality of curved void strips 25 form a grid curve on the metallized film 2;

The above-mentioned sheet metallized film 1 is taken as an example. Referring to FIG. 5 and FIG. 6 , the center-side gap of the curved-shaped gap strip 15 is bent into a shape of a notch 151, and the notch opening faces the right side, and the two sides of the notch 151 are dislocated. The shoulder shape of the distribution; of the two curved gap strips adjacent to each other, the end point B at the leftmost side of the right curved void strip enters at least the recess 151 of the left curved void strip.

The width of the curved void strip is greater than or equal to 0.1 mm; the width of each curved void strip may be equal or unequal. In this embodiment, the width of each curved void strip is equal.

The curved void strip 15 is composed of a first curved void strip L1, a second curved void strip L2, a third curved void strip L3, and a fourth curved void strip L4 which are integrally connected in series.

Wherein, the fourth curved type gap strip L4 is a curved section between a preset position E of the curved gap strip to the left edge of the metallized film, and the second curved type gap strip L2 is after the fourth curved type gap strip is removed a curved section between the end point at the leftmost side of the curved gap section and the end point of the rightmost side, that is, the second curved type gap strip L2 is the end point A to the curved type at the rightmost side of the curved gap strip a curved section between the end points B at the leftmost side of the gap strip;

In the present embodiment, the upper metallized film 1 is formed with the notch opening facing the right side. Therefore, the first curved type gap strip L1 is one end of the curved gap segment after the fourth curved type gap strip is removed to the curved type. a curved section between the end points A at the far right side of the gap section, and the third curved type gap strip L3 is the end point B at the leftmost side of the curved gap section after the fourth curved type gap strip is removed to the curve A curved section between preset positions in a type of gap strip.

In the adjacent upper and lower metallized films, the film width of the upper metallized film 1 is set to b1, and the distance from the preset position on the upper metallized film 1 to the edge of the film on the remaining side is set to B11, the width of the upper metallized film 1 with respect to the lower metallized film 2 is b12; the film width of the lower metallized film 2 is set to b2, and the preset position on the lower metallized film 2 is The distance between the edges of the film on the left side is set to b21. The width of the lower metallized film 2 relative to the upper metallized film 1 is b22; the following formula should be satisfied between them:

B11+b12+b21>b1

B21+b22+b11>b2

In this embodiment, the film widths of the adjacent upper and lower metallized films are the same, the width of the wrong side is also equal, and the distance from the preset position to the edge of the film on the left side is also the same:

B1=b2, b12=b22, b11=b21;

B11>[b1-b12]/2;

B21>[b2-b22]/2.

One end of the first curved void strip L1 is connected to the second curved void strip L2, and the other end of the first curved void strip L1 is provided with an end edge of the metallized film or an end of the metallized film. A preset distance. In this embodiment, the other end of the first curved type gap strip L1 and the edge of the metallized film are provided with a preset distance b13. Of course, another design may be adopted, that is, the first curved type gap strip L1. The other end of the metal film is opened to the end, which is equivalent to b13 ≥ 0.

The length of the first curved type void strip L1 may be designed to be greater than or equal to 0 mm.

The end point on the left side of the preset position on the fourth curved type gap strip L4 is set to C, and the end point on the right side of the L4 preset position on the fourth curved type gap strip is D.

In the two adjacent curved gap strips, as shown in FIG. 5, the rightmost curved strip has the end point B2 at the leftmost side of the curved void strip after the fourth curved void strip is removed. The left side of the end point D1 at the right side of the preset position on the fourth curved type gap strip of the gap strip, of course, the right side of the curved type gap strip after the fourth curved type gap strip is removed The end point B2 at the position is flush with the end point D1 on the right side of the preset position on the fourth curved type gap strip of the left curved type gap strip, and is equivalent to being set to b14 ≥ 0.

In the two adjacent curved gap strips, as shown in FIG. 5, the rightmost point C3 of the metal plating between the adjacent left and right curved lines is stripped of the fourth curved gap in the left curved gap strip. The left side of the rightmost end point A2 of the curved gap section after the strip; of course, it may be the rightmost point C3 of the metal plating between the adjacent left and right curved lines, and the left curved type gap strip The rightmost end point A2 of the curved gap section after the fourth curved type gap strip is flush; the equivalent is set to b15 ≥ 0.

One end of the fourth curved type gap strip L4 is connected to the third curved type gap strip L3, and the other end of the fourth curved type gap strip L4 is connected to the left side 101 of the metallized film. In this embodiment, the fourth curved type gap strip L4 is a straight line segment of the vertical film edge.

The positional relationship between adjacent grid curves (ie, curved gap strips), b16 is the width of the curve, and b17 is the distance between the grid curves. B16 ≥0.1mm, b17 can be unequal spacing, but adjacent curves should satisfy b14 ≥ 0 and b15 ≥ 0.

Adjacent upper and lower metallized films, the metal plating of the upper metallized film 1 is connected to the first electrode, and the metal plating of the lower metallized film 2 is connected to the second electrode.

At the left side, the metal plating layer 1.1, the metal plating layer 1.2, and the metal plating layer 1.3 are connected to the first electrode, and the metal plating layer 1.4 is not connected to the first electrode. The metal plating layer 2.1, the metal plating layer 2.2, and the metal plating layer 2.3 are connected to the second electrode, and the metal plating layer 2.4 is not connected to the second electrode.

At the right cut surface, the metal plating layer 1.5 is connected to the first electrode, and the metal plating layer 1.6, the metal plating layer 1.7, and the metal plating layer 1.8 are not connected to the first electrode. The metal plating layer 2.5 is connected to the second electrode, and the metal plating layer 2.6, the metal plating layer 2.7, and the metal plating layer 2.8 are not connected to the second electrode.

On the cut surface, at least the metal plating (1.4, 1.8, 2.4, 2.8) near the left side is not connected to the electrode. B18 ≥ b11, b19 ≥ b11, b28 ≥ b21, b29 ≥ b21.

On the tangential surface, the shortest insulation distance b31, b32 between the first electrode and the second electrode.

Like the upper and lower two metallized films, the preset position E is the same. B1=b2, b12=b22, b11=b21.

B31=b18+b28+b12-b1

B32=b19+b29+b12-b1

From b1=b2, b12=b22, b11=b21, b18≥b11, b19≥b11, b28≥b21, b29≥b21, get:

B31≥2b11+b12-b1

B32 ≥ 2b11 + b12-b1

At preset position E, b11>(b1-b12)/2

So: b31>0, b32>0

On the tangential surface, the shortest insulation distance b31, b32 of the first electrode and the second electrode, according to the design, b31, b32 is much larger than the thickness of the medium between the electrodes, and the withstand voltage is proportional to the insulation distance, thereby increasing the laminated metallized film capacitance. The cut surface of the core is pressure resistant.

In the present embodiment, the underlying metallized film 2, as shown in FIG. 7, is conventionally used. For a single metallized film, the margin is viewed on the bottom side, and therefore, the notched shape of the metallized film 2 is obtained. The notch opening faces the left side; b24 in FIG. 7 is the same as b14 in FIG. 5, and b25 in FIG. 7 is the same as b15 in FIG.

In this embodiment, the cross-sectional direction of the laminated metallized film capacitor core is consistent with the longitudinal direction, that is, the preset angle is zero degrees, and the curved gap strip is disposed in the longitudinal direction. Of course, the curved gap strips can also be set at a predetermined angle along the longitudinal direction of the offset. At this time, the direction of the cut surface of the laminated metallized film capacitor core is at an angle to the longitudinal direction, so that all the curved gap strips Both form an angle with the longitudinal direction (as shown in FIG. 8). In FIG. 8, the curved gap strip 55 of the metallized film 1 is reversely twisted to the same angle as in FIG. 5, and is arranged in the longitudinal direction when the curved gap strip is arranged. The condition that the structure is offset from the longitudinal direction of the angle, there is also a predetermined distance between the first electrode and the second electrode; b5 is the film width of the metallized film 1, and the metallized film 5 is The distance from the preset position E to the edge of the film on the side of the remaining side 501 is set to b51.

Embodiment 2 Referring to FIG. 9, the electrode structure of a laminated metallized film capacitor of the present invention is different from that of Embodiment 1 in that other electrode structures 61 are added between the grid curves to improve the product. Performance.

Embodiment 3, referring to FIG. 10 to FIG. 11, the electrode structure of a laminated metallized film capacitor of the present invention can also be improved by using the same electrode structure for a plurality of stacked metallized film capacitors. The cut surface pressure resistance of the laminated metallized film capacitor core.

In this embodiment, the upper metallized film 3 includes a conductive metal plating layer 30 and an insulating dielectric layer 300. The conductive metal plating layer 30 is coated on the insulating dielectric layer 300, and the underlying metallized film 4 includes a conductive metal plating layer 40. And an insulating dielectric layer 400, the conductive metal plating layer 40 is coated on the insulating dielectric layer 400; the upper metallized film 3 is provided with the longitudinal gap strip 31 in the middle, and each of the two sides is provided with a plurality of strips as described in the first embodiment. Curved void strips 32; the lower strip metallized film 4 has longitudinal gap strips 41 disposed on both sides, and a plurality of curved gap strips connected by two curved gap strips 42 as described in the first embodiment. .

Industrial applicability

The structure of the invention increases the insulation distance between the metallized electrodes of different potentials on the cut surface of the capacitor core, and can improve the cut surface pressure resistance of the laminated metallized film capacitor core.

The above embodiments are only used to further explain the electrode structure of a laminated metallized film capacitor of the present invention, but the present invention is not limited to the embodiment, and any simple modification of the above embodiment in accordance with the technical essence of the present invention is provided. Equivalent changes and modifications are all within the scope of protection of the technical solutions of the present invention.

Claims

An electrode structure of a laminated metallized film capacitor comprising at least two metallized films laminated together; adjacent upper and lower metallized films are stacked in a longitudinal direction to have a staggered state with a predetermined wrong width Each of the metallized films respectively comprises a conductive metal plating layer and an insulating dielectric layer, and the conductive metal plating layer is coated on the insulating dielectric layer; at least one uncoated metal plating layer is provided on each metallized film along the lateral direction. And a gap strip having a width, the void strip constituting a margin of the metallized film; characterized by:

On each metallized film, a plurality of curved gap strips which are not covered with metal plating and have a certain width are arranged along the cutting plane direction of the laminated metallized film capacitor core to connect adjacent metal plating units Partially spaced or completely separated; the curved gap strip has a concave shape in the middle, the two sides of the recess form a shoulder shape with a misaligned distribution, and the opposite direction of the recess opening is convex; in the adjacent two curved gaps In the strip, the most convex end of one of the curved void strips enters at least the recess of the other curved void strip.
The electrode structure of the laminated metallized film capacitor according to claim 1, wherein the shape of the notch of the curved gap strip of the adjacent upper and lower two metallized films, the orientation of the notch opening For the same direction or different directions.
The electrode structure of the laminated metallized film capacitor according to claim 1, wherein: the adjacent upper and lower metallized films, the metal plating of the upper metallized film is connected to the first electrode, A metallization of a metallized film is attached to the second electrode, and a predetermined distance exists between the first electrode and the second electrode on the tangential surface.
The electrode structure of a laminated metallized film capacitor according to claim 1, wherein the width of each of the curved void strips is equal or unequal, and the width of each curved void strip is greater than or equal to 0.1 mm.
The electrode structure of a laminated metallized film capacitor according to claim 1, wherein the curved gap strip is formed by a first curved gap strip, a second curved void strip, and a plurality The three-curve type void strip and the fourth curved type void strip are formed.
The electrode structure of a laminated metallized film capacitor according to claim 5, wherein:

The curved gap strip is disposed along a cross-sectional direction of the laminated metallized film capacitor core, and the cut surface direction is at a predetermined angle with the longitudinal direction, and the cut surface and the curved gap strip are reversely twisted by the preset angle When the cutting plane direction is consistent with the longitudinal direction, the first curved gap strip, the second curved void strip, the third curved void strip, and the fourth curved void strip satisfy the following conditions:

The fourth curved type gap strip is a curved section between a preset position in the curved gap strip to the trailing edge of the metallized film, and the second curved type gap strip is a curved type gap strip after the fourth curved type gap strip is removed a curved segment between the endpoint at the far left of the segment and the endpoint at the far right;

With the notch opening facing the left side, the first curved type gap strip is a curved section between the end of the curved gap section after the fourth curved type gap strip is removed to the leftmost end of the curved gap section a third curved type gap strip is a curved line between an end point at a rightmost side of the curved gap strip segment after the fourth curved type gap strip is removed to a preset position in the curved type gap strip;

With the notch opening facing the right side, the first curved type gap strip is a curved section between the end of the curved gap section after the fourth curved type gap strip is removed to the rightmost end of the curved type of void section The third curved type void strip is a curved section between the end point of the leftmost curved portion of the curved void strip after the fourth curved type void strip is removed to a preset position in the curved gap strip.
The electrode structure of a laminated metallized film capacitor according to claim 6, wherein in the adjacent upper and lower metallized films, the film width of the upper metallized film is set to b1. The distance from the preset position on the metallized film to the edge of the film on the left side is set to b11, and the width of the upper metallized film relative to the lower metallized film is b12; the film of the next metallized film is set. The width is b2, the distance from the preset position on the lower metallized film to the edge of the film on the side of the remaining side is b21, and the width of the lower metallized film relative to the upper metallized film is b22; The following formula should be met:

B11+b12+b21>b1

B21+b22+b11>b2

When the film widths of the adjacent upper and lower metallized films are the same, the widths of the wrong sides are also equal, and when the distance from the preset position to the edge of the film on the left side is also the same, then:

B1=b2, b12=b22, b11=b21;

B11>[b1-b12]/2;

B21>[b2-b22]/2.
The electrode structure of a laminated metallized film capacitor according to claim 6, wherein one end of the first curved void strip is connected to the second curved void strip, and the first curved void strip is further One end of the metallized film is provided with an end edge or a predetermined distance from the end of the metallized film;

The preset distance is greater than or equal to 0 mm;

The length of the first curved void strip is greater than or equal to 0 mm.
The electrode structure of a laminated metallized film capacitor according to claim 6, wherein: the two adjacent curved gap strips;

Regardless of the notch orientation, the right curved type gap strip excludes the leftmost end point of the curved gap section after the fourth curved type gap strip and the right end position of the fourth curved type gap strip of the left curved type gap strip. The end point at the side is flush, or the left end of the curved gap strip after the fourth curved gap strip is removed from the leftmost edge of the curved gap strip is preset on the fourth curved gap strip of the left curved gap strip. The left side of the endpoint at the right side of the position.

Regardless of the notch orientation, the left curved groove strip excludes the rightmost end point of the curved gap segment after the fourth curved gap strip and the left end of the fourth curved void strip of the right curved void strip. The end points at the sides are flush, or the leftmost end of the curved gap strip after the left curved gap strip is removed from the fourth curved gap strip is preset on the fourth curved gap strip of the curved outer gap strip. The right side of the endpoint at the left side of the position.
The electrode structure of a laminated metallized film capacitor according to claim 6, wherein one end of the fourth curved void strip is connected to the third curved void strip, and the fourth curved void strip is further One end is connected to the left side of the metallized film;

Regardless of the notch orientation, the rightmost point of the curved gap section after the fourth curved gap strip is removed from the rightmost point of the adjacent left and right four curved stripe strips and the left curved stripe strip Flush; or the rightmost point of the metal plating between the adjacent left and right 4th curved gap strips is left at the rightmost end of the curved void strip after the left curved void strip is removed from the fourth curved void strip side;

Regardless of the notch orientation, the leftmost point of the curved gap section after the fourth curved type gap strip is removed from the leftmost point of the adjacent left and right second curved type interstitial strips and the left curved point of the left curved type gap strip Flush; or the leftmost point of the metal plating between the adjacent left and right 4th curved gap strips is on the right side of the leftmost end of the curved void strip after the fourth curved void strip is removed side.